|
| US3995381 | 27. Juni 1975 | 7. Dez. 1976 | | Low visibility answer sheet and method of testing |
| US4007354 | 13. März 1975 | 8. Febr. 1977 | | Calculator and medium with commands for calculator operation |
| US4270043 | 13. März 1979 | 26. Mai 1981 | Kronos Inc. | Methods of and apparatus for time clock recording and computation and related uses |
| US5001330 | 2. März 1988 | 19. März 1991 | National Computer Systems, Inc. | Optically scanned document with fail-safe marking |
| US5076718 | 27. Dez. 1990 | 31. Dez. 1991 | Seikosha Co., Ltd. | Data card for serial printer |
| US5103490 | 13. Juni 1990 | 7. Apr. 1992 | National Computer Systems, Inc. | Method and apparatus for storing and merging multiple optically scanned images |
| US5134669 | 13. Juni 1990 | 28. Juli 1992 | National Computer Systems | Image processing system for documentary data |
| US6996365 | 13. Aug. 2002 | 7. Febr. 2006 | Kabushiki Kaisha Nihon Toukei Jim Center | Scoring method and scoring system |
